4sinxcosx=√2,
2sin2x=√2,
sin2x=√2/2,
2x=(-1)^n·π/4+πn, n-любое целое число,
x=(-1)^n·π/8+πn/2.
3,7 - 2х = 3х - 1,8
- 2х - 3х = - 1,8 - 3,7
- 5х = - 5,5
х = (- 5,5) : (- 5)
х = 1,1
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3,7 - 2 * 1,1 = 3 * 1,1 - 1,8
3,7 - 2,2 = 3,3 - 1,8
1,5 = 1,5
А) 9081+15700+919=(9081+919)+15700=10000+15700=25700
б) (652+59300)+48=652+59300+48=(652+48)+59300=700+59300=60000
в) 3977+1940+23+60=(3977+23)+(1940+60)=4000+2000=6000
г) 359+(7987+241)+2013=359+7987+241+2013=(2987+2013)+(359+241)=5000+600=5600
DBE=5<span>0º-30%=35<span>º</span></span>
<span><span>5<span>0º-40%</span></span></span>
х-100%
х=50*100:40=125<span>º ABC</span>
ABD=125<span>º-5<span>0º-35<span>º=4<span>0º</span></span></span></span>
<em>(246+а) - 46 = 644</em>
<em>246 +а = 644 + 46</em>
<em>246 + а = 690</em>
<em>а = 690 - 246</em>
<em>а = 444</em>